This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. We are developing a low coherence Fourier domain phase microscope (FDPM) for reflection-mode studies of cell electromotility. Classical FDPM implementations employ common-path configuration in which the glass coverslip surface farther from the biological sample serves as a reference reflector. The common-path FDPM systems, however, compromise with the spatial resolution by using relatively low NA microscope objectives to simultaneously collect optical signal from the specimen as well as the reference surface. The use of low NA microscope objectives also results in relatively stronger optical signal from glass coverslip surface adjacent to the biological sample, hence leading to diminished phase measurement from the specimen. Moreover, the common-path FDPM systems use point illumination and fall into the category of single lateral point measurement techniques. To overcome the limitations of point illumination common-path FDPM setups, we propose a phase-sensitive low coherence phase microscope with line-field illumination and a separate reference arm. The line-field illumination will not only allow self-phase referencing for common-mode noise rejection but also simultaneous depth-resolved phase measurement of multiple lateral locations. Only one-dimensional beam scanning will be required for two-dimensional phase imaging of biological sample, if desired.